Application of photopharmacology in agrochemicals

Photopharmacology is a novel technology in drug design that aims at solving poor drug selectivity. This technology is currently in the proof-of-concept phase and relies on the photoactivation or inactivation of photochromic ligands (PCLs) to regulate biological functions and living organisms. As potential molecular tools in future agriculture 4.0, the photochromic pesticides are effective in optical control of receptors, ion channels, living behaviors, and enzymes, which displays an innovative way of pesticide discovery. In this review, we highlight the progresses of the photoisomerized insecticides and fungicides. By integrating photoswitches, such as azobenzenes and diarylethenes, into pesticide molecules, several PCLs were developed for optical regulation of important insect or fungi targets in vivo, including GABARs, RyRs, nAChRs, SURs, sodium channels, GluCls, and SDH. The results are highly significant in revealing interactions of agrochemicals with their targets, biological functions, and living behaviors, and provide powerful toolkits in understanding ligand-receptor interactions. Moreover, there is a growing demand for a diverse range of PCLs, particularly those that are sensitive to red and NIR light or sunlight, for actual field use in agriculture. We envision that this particular mode of pesticide discovery is of great promise for overcoming the challenges posed by the improper use of agrochemicals.